Calibration Equipment

Jeti Specbos 1211 Broadband Spectroradiometer

The Jeti Specbos 1211 is the most desirable spectroradiometer available to video calibrators today. It is an extremely accurate miniaturized spectroradiometer. The Specbos is capable of taking readings more quickly than older spectroradiometers such as our PR-650. The 1211 can take accurate measurements of light between the wavelength of 350 nm to 1000 nm.

Another outstanding feature of the 1211 is that its optical resolution is incredibly fine at just 4.5 nm. Fine resolution may be important on certain types of digital displays for achieving an accurate color gamut. In comparison, the standard Photo Research models PR-650, 655, and 670 only have optical resolutions down to 8 nm, or 5 nm with high resolution upgrades. Since the Jeti 1211 is capable of an such fine optical resolution, it will be more accurate on more types of digital displays as the technology evolves and moves forward.

Since the 1211 is miniature it’s nicely portable and considering that the Jeti is more accurate than the Photo Research meters it has become our primary go-to spectroradiometer in the field. Typically the 1211 is used to create “offsets” for white and the three primary colors. These offsets are used in our ChromaPure software to adjust the accuracy of the Klein K10-A colorimeter (see the K10-A below). This allows the Klein to have more accuracy than a colorimeter typically provides. Together, the Specbos 1211 and Klein K10-A combine to create an amazing team of instrumentation that allows for the most accurate measurements possible, to take readings quickly, and suitable for both low stimulus (dark images) and high stimulus (bright images).

There is simply no way to get a more accurate video calibration than with a Jeti 1211 Specbos taking the initial readings. This meter is truly top notch.

Photo Research PR-650 SpectraScan Spectroradiometer

The PR-650 is a research-grade spectroradiometer, making it a premier spectroradiometer available to video calibrators. For decades, Photo Research has been making some of the most accurate portable spectroradiometers in the world.

Because the PR-650 is a true spectroradiometer, it can be used to accurately measure most types of display technology including DLP, LCD, LED, or CRT. The PR-650 is good for taking light readings on displays from about 30% light stimulus all the way up to 100% stimulus. The PR-650 may be used by CIR Engineering to calibrate such variables as grayscale, gamma, brightness, contrast, and color gamut. It is one of our reference meters, and as such can also be used to measure “offsets” that will be applied to our Klein K10-A colorimeter (more about that under the K10-A meter section).

Klein K10-A Colorimeter

The K10-A uses a different type of technology than the Jeti 1211 or the PR-650. The Klein K10-A is a colorimeter, while the others are true spectroradiometers. The two primary strengths of the Klein are accuracy at extremely low light levels all the way down to 0.00002 foot-lambert, and also the ability to take readings incredibly quickly. The K10-A also has high repeatability, meaning that when measuring the same stimulus over and over, the meter will return the same value again and again.

The typical weakness of colorimeters is that they are limited by their design and are not typically accurate on different types of display technologies. For example, a colorimeter that is designed to be used on LCD will typically not do well when it is used for measuring a DLP projector. However, if another more accurate spectroradiometer can be used on the job site to provide “offsets” for the Klein, then the Klein will be nearly as accurate as the reference spectroradiometer. This combination of tools will provide the benefits of low light capability and fast readings while maintaining reference spectroradiometer accuracy.

Because of this, the Klein K10-A is used by CIR Engineering in combination with the Jeti 1211 or PR-650. Typically the Klein will be applied during Lumagen Radiance calibrations when using the 5x5x5 matrix (125 point calibration). This is paramount because a spectroradiometer takes readings comparatively slowly and cannot possibly be used for a 125 point calibration (it would take more than 12 hours). During a 125 point calibration multiple iterations may be required so the measurement process usually needs to be repeated several times. In addition, on a 125 point calibration stimulus levels below 30% must be calibrated and the K10-A is the correct tool for this part of the job.

The Klein will most likely be used during every calibration, especially when the display has anything more than a two point grayscale adjustment. This includes a full color management system (CMS) and ten point grayscale adjustments.

Quantum Data QD780

The QD780 is without question the most powerful portable video generator in the world. It is also an excellent audio generator as well as an HDMI analyzer. The QD780 has a prolific array of test patterns and can also display custom patterns that CIR Engineering has designed for specific calibration applications. The 780 is capable of displaying both 2D and 3D patterns and can even display custom 3D patterns and still images.

Video test patterns generated by the QD780 can be relied on to meet industry video standards. This ensures that the calibration of your display will work with any video equipment that meets industry standard. In the event that certain variables are not working properly due to a limitation in a specific home theater, the QD780 can be utilized to help identify these shortcomings. Once a limitation is understood in a given display device or video chain, a solution can be devised to mitigate any problems that your particular system may experience.

DVDO AVLab TPG 4K UltraHD Test Pattern Generator

This is a small form factor, portable, 4K, UltraHD, HDMI 2.0. video test pattern generator. The TPG 4K is the newest tool in our arsenal and can be used to supply native 4K test patterns all the way up to 60Hz. The TPG 4K can also supply 24Hz test patterns as well as HD test patterns.

A unique feature of this pattern generator is that it will allow a split screen to be displayed between a source pass through and a test pattern from the generator. This is an incredibly valuable feature for calibrating source devices that can supply their own test patterns such as BluRay players with a test pattern disc, or satellite providers who broadcast test patterns. In this way, the sources test patterns can be directly compared to the pattern generator on the display screen. Differences are obvious especially when looking at problems that can be seen with color bars.

The TPG 4K is also compatible with Chromapure and can be used in automated calibrations with the software.

ChromaPure Professional Calibration Software

ChromaPure is one of the newest and most dynamic professional calibration software suites available to video engineers. It is an invaluable tool which utilizes and integrates all of our calibration equipment to provide data on the display device.

ChromaPure is what controls and drives the spectroradiometers (Jeti Specbos and Photo Research) and colorimeter (Klein). The software displays readings from the instruments on the PC screen, providing the calibrator with quantitative information on exactly what the display is doing. ChromaPure may be used in the calibration of such parameters as grayscale, gamma, color, color gamut, and much more. It can also be used in auto-calibration mode with a Lumagen Radiance processor to perform a 125 point calibration.

At the end of your calibration ChromaPure will also be used to generate reports on your calibration. Typically both before and after calibration reports will be provided. This way you will know quantitatively where your display came from and just how accurate it is after the work is done.

Tektronix Digital and Analog Oscilloscopes

Tektronix has been one of the most highly regarded names in test equipment for decades. An oscilloscope is one of the most diverse pieces of test equipment in existence. When performing video calibrations, the scope may be used to help set and test many parameters, include sharpness and color decoding. However, with modern displays, the oscilloscopes are usually only used for repair or hardware modifications.

DVE BD, Spears & Munsil BD, AVIAPro DVD, DVE DVD, DVE LD

These test discs will be used to see how well a BluRay, DVD, or LaserDisc player conforms to industry standard. If the player is of good quality, it will follow industry guidelines and should perform well when combined with a calibrated display. These test discs will help expose problems coming from the source. In some cases the player itself can then be adjusted, or corrections may be made in your video processor or even in the display itself.